U.S. patent application number 13/015926 was filed with the patent office on 2011-10-06 for endoscopic gaseous material feed system.
Invention is credited to Kentaro HAYASHI, Mutsumi NARUSE.
Application Number | 20110245606 13/015926 |
Document ID | / |
Family ID | 44710429 |
Filed Date | 2011-10-06 |
United States Patent
Application |
20110245606 |
Kind Code |
A1 |
HAYASHI; Kentaro ; et
al. |
October 6, 2011 |
ENDOSCOPIC GASEOUS MATERIAL FEED SYSTEM
Abstract
An endoscopic gaseous material feed system comprises a gas
feeder 3 having a gas tank 60 containing carbon dioxide gas, a
light source 2 incorporating an air pump 23 for air supply, an
endoscope 1 internally having a gaseous material passage for a gas
or air supply to a body cavity of a patient or examinee, and a
controller 80 adapted to put the air pump 23 of the light source 2
in a deactivated state upon detection of a start of a carbon
dioxide gas supply from the gas feeder 3.
Inventors: |
HAYASHI; Kentaro; (Kanagawa,
JP) ; NARUSE; Mutsumi; (Kanagawa, JP) |
Family ID: |
44710429 |
Appl. No.: |
13/015926 |
Filed: |
January 28, 2011 |
Current U.S.
Class: |
600/109 ;
600/158 |
Current CPC
Class: |
A61B 1/0661 20130101;
A61B 1/015 20130101 |
Class at
Publication: |
600/109 ;
600/158 |
International
Class: |
A61B 1/015 20060101
A61B001/015; A61B 1/045 20060101 A61B001/045 |
Foreign Application Data
Date |
Code |
Application Number |
Mar 31, 2010 |
JP |
2010-081713 |
Claims
1. An endoscopic gaseous material feed system, comprising: a gas
feeder having a gas tank packed with carbon dioxide gas; a light
source incorporating an air pump for air supply; an endoscope
internally formed with a gaseous material passage to supply carbon
dioxide gas or air to a body cavity of a patient or examinee; and a
controller adapted to put said air pump of said light source in a
deactivated state upon detection of a start of a carbon dioxide gas
supply from said gas feeder.
2. An endoscopic gaseous material feed system as set forth in claim
1, further comprising: a processor adapted to process video signals
of endoscopically captured picture images on the basis of electric
signals from a solid-state image sensor mounted on a distal end
portion of said endoscope; said controller being provided in said
processor electrically connected with said light source and said
gas feeder.
3. An endoscopic gaseous material feed system as set forth in claim
2, wherein said controller is adapted to suspend a supply of carbon
dioxide gas from said gas feeder as soon as a residual gas content
in said gas tank drops below a predetermined threshold value, while
activating said air pump to start an air supply from said light
source.
4. An endoscopic gaseous material feed system as set forth in claim
3, wherein, on a manipulating head assembly, said endoscope is
provided with a gas feed conduit at a junction of a carbon dioxide
gas supply route from said gas feeder and an air supply route from
said light source, a liquid feed conduit adopted as a passage of a
liquid delivered from a liquid feed tank under pressure applied by
said carbon dioxide gas or air on a liquid surface in said liquid
feed tank, and a fluid feed valve adapted to selectively take in
either a feed gas delivered under pressure through said gas feed
conduit or a feed liquid delivered under pressure through said
liquid feed conduit; said fluid feed valve being adapted to permit
replacement of an open-to-atmosphere type fluid feed valve in
communication with the atmosphere for release of a gas in said gas
feed conduit, by a closed-to-atmosphere type fluid feed valve
blocking communication of said gas feed conduit with the
atmosphere, or vice versa.
5. An endoscopic gaseous material feed system as set forth in claim
2 or 3, further comprising a relief mechanism to relieve pump
pressure of said air pump to the atmosphere when reached beyond a
predetermined upper limit.
6. An endoscopic gaseous material feed system as set forth in claim
2 or 3, further comprising a main power switch to turn on and off
said gas feeder and said light source together, said controller
being adapted to start a carbon dioxide gas supply from said gas
feeder when said main power switch is turned on, while suspending
an air supply from said air pump.
Description
FIELD OF THE INVENTION
[0001] This invention relates to an endoscopic gaseous material
feed system for medical use, having a gas feeder to supply carbon
dioxide gas to an endoscope which is connected to a light source
having an air supply source.
BACKGROUND OF THE INVENTION
[0002] In endoscopy, air or a gas, as a gaseous material, is
supplied to a body cavity of a patient or examinee for the purpose
of securing a view field of an endoscope or for securing a space
which is required for manipulation of a surgical or biopsy tool as
an unlimited source of gaseous material. Heretofore, it has been
the general practice to use air as a gas to be delivered to a body
cavity. However, instead of air, carbon dioxide gas (CO.sub.2) is
increasingly used for this purpose, in consideration of better in
vivo absorption and less damages to a patient or examinee.
[0003] Air is delivered to a body cavity from an air pump which is
provided internally of a light source enclosure. On the other hand,
carbon dioxide gas is delivered from a gas tank which is packed
with carbon dioxide gas and replaceably loaded on a gas feeder. A
gas feed system having such light source and gas feeder is
disclosed in Japanese Laid-Open Patent Application 2006-14961.
According to this technology, a gas feeder and a light source are
connected with each other by way of a gas tube to supply an
endoscope selectively with air from an air pump or carbon dioxide
gas from the gas feeder through a control mechanism provided inside
the light source.
[0004] In this case, a selector switch is provided on an operation
panel on the light source thereby to make a selection between air
and carbon dioxide gas in starting a gas supply to a body cavity,
controlling the connected light source and gas feeder to effectuate
a supply of a selected gas. The light source and the gas feeder are
communicable with each other by way of a communication cable. When
air is selected by the selector switch, an electromagnetic valve of
the gas feeder is closed to make a supply of carbon dioxide gas
infeasible, while the air pump is put in operation for an air
supply. On the other hand, when carbon dioxide gas is selected, the
above-mentioned electromagnetic valve is opened to start a supply
of carbon dioxide gas, while the air pump is held in a deactivated
state.
[0005] The light source and gas feeder are separate units and
separately turned on and off by the gas feed system. The light
source, i.e. an illumination light source, is always kept on as
long as an endoscopic examination or treatment is underway,
irrespective of activation and deactivation of the air pump. That
is, without exception, the power source of the light source is
always turned on at the time of an endoscopic examination or
treatment. On the other hand, for a carbon dioxide gas supply, the
power source of the gas feeder is turned on to supply carbon
dioxide gas from the gas tank. At this time, the light source is
left on.
[0006] Within an enclosure of the light source, an air supply route
and a gas supply route are joined together. That is to say, there
is a possibility that air and carbon dioxide gas are simultaneously
put in supply by an erroneous operation although it is a requisite
to supply a selected gas alone. In Japanese Laid-Open Patent
Application 2006-14961 mentioned above, arrangements are made to
preselect one of the two feed gaseous materials by way of a
selector switch. Therefore, at the time of switching the feed gas
from air to carbon dioxide gas, it becomes necessary to turn on the
power source of the gas feeder and at the same time to depress the
selector switch for a switch to carbon dioxide gas, thus involving
two kinds of switching operations for a switch of the feed gaseous
material.
[0007] In case a selector switch is provided on a light source as
in Japanese Laid-Open Patent Application 2006-14961, it becomes
necessary to operate two different switches at two different
locations. Especially, it is extremely troublesome to operate two
different switches on the light source and gas feeder which are
mounted separately on two carts or mounted jointly on one and same
cart, one on the upper side of the other, as shown in FIG. 20 of
Japanese Laid-Open Patent Application 2006-14961.
SUMMARY OF THE INVENTION
[0008] With the foregoing in view, it is an object of the present
invention to provide an endoscopic gaseous material feed system,
which is capable of switching a feed gaseous material between
carbon dioxide gas and air in such a way as to lessen burdens on
the part of an operator.
[0009] In order to achieve the above-stated objective, according to
the present invention, there is provided an endoscopic gaseous
material feed system, comprising: a gas feeder having a gas tank
packed with carbon dioxide gas; a light source incorporating an air
pump for air supply; an endoscope internally provided with a
gaseous material passage to supply carbon dioxide gas or air to a
body cavity of a patient or examinee; and a controller adapted to
hold the air pump of the light source in a deactivated state upon
detection of a start of carbon dioxide gas supply from the gas
feeder.
[0010] According to this endoscopic gaseous material feed system,
the controller is adapted to take preference of a carbon dioxide
gas, as one of gaseous material, supply from the gas feeder over an
air, as another gaseous material, supply from the light source when
a supply of whichever gas is feasible. Since the air pump is
automatically in put in a deactivated state upon starting a supply
of carbon dioxide gas, the operator has no need for manually
turning off the air pump. Thus, the feed gas can be switched in
such a way as to lessen burdens on side of an operator.
[0011] In a preferred form of the invention, the endoscopic gaseous
material feed system further comprises a processor which is adapted
to perform video signal processing operations to produce video
signals of endoscopically captured picture images on the basis
electric signals from a solid-state image sensor device provided at
a fore distal end of the endoscope, and the above-mentioned
controller is incorporated into the processor which is electrically
connected with the gas feeder and the light source.
[0012] In this instance, the controller is incorporated into the
processor, which is electrically connected with the light source
having an air pump to be put in operation for an air supply, as
well as with the gas feeder to be put in operation for a carbon
dioxide gas supply. On the other hand, the processor usually
incorporates a processor unit which is capable of performing
complicate signal processing operations. Therefore, such a
processor unit can be utilized to perform the functions of the
above-mentioned controller of the gaseous material feed system.
That is to say, the controller of the gaseous material feed system
can be realized by reconstructing existing gas feeder and light
source without adding a complicate construction.
[0013] In another preferred form of the invention, the controller
is adapted to suspend a carbon dioxide gas supply from the gas
feeder upon detection of residual gas content in the gas tank
dropping below a predetermined threshold value, while activating
the air pump of the light source to start a supply of air.
[0014] According to this endoscopic gaseous material feed system,
carbon dioxide gas is preferentially used as a feed gas but its
source (a gas tank) has a limit and may become deficient.
Therefore, when residual gas content in the gas tank drops below a
predetermined threshold value, the gas feed is switched to air to
avoid an interruption of an ongoing endoscope examination or
treatment.
[0015] In another preferred form of the invention, the endoscope is
internally provided with a gas feed conduit connected to a junction
of a carbon dioxide gas supply route from the gas feeder and an air
supply route from the light source, a liquid feed conduit adopted
as a passage of a liquid delivered from a liquid feed tank under
pressure applied by the carbon dioxide gas or air on a liquid
surface in the liquid feed tank, and a fluid feed valve adapted to
selectively take in either a feed gas delivered under pressure
through the gas feed conduit or a feed liquid delivered under
pressure through the liquid feed conduit; the fluid feed valve
being adapted to permit replacement of an open-to-atmosphere type
fluid feed valve in communication with the atmosphere for release
of a gas in the gas feed conduit, by a closed-to-atmosphere type
fluid feed valve blocking communication of the gas feed conduit
with the atmosphere, or vice versa.
[0016] In this case, the fluid feed valve is replaceable by a
different type. At the time of feeding carbon dioxide gas, a
closed-to-atmosphere type fluid feed valve is set on the endoscope
to prevent wasteful consumption of carbon dioxide gas. On the other
hand, at the time of feeding air, an open-to-atmosphere type fluid
feed valve is set on the endoscope to release an excessively
elevated pump pressure. Therefore, it is made possible to choose a
fluid feed valve between two different types to carry out an
endoscopic examination or treatment in a favorable manner.
[0017] In a preferred form of the invention, the endoscopic gaseous
material feed system further comprises a relief mechanism for the
purpose of relieving pump pressure of the air pump to the
atmosphere when reached beyond a predetermined upper limit.
[0018] In this case, an excessive buildup of pressure is released
to the atmosphere by the relief mechanism. A buildup of an
excessively high pressure can occur when the air pump is
erroneously put in operation during a closed-to-atmosphere type
fluid feed valve is set on the endoscope. On such an occasion, an
excessively high pressure is automatically released into the
atmosphere through the relief mechanism.
[0019] In another preferred form of the invention, the endoscopic
gaseous material feed system further comprises a main power switch
thereby to turn on and off the gas feeder and said light source
together, the controller being adapted to start a carbon dioxide
gas supply from the gas feeder when the main power switch is turned
on, while suspending an air supply from the air pump.
[0020] In this case, by the provision of the main power switch
which turns on the two gas sources together, the endoscopic gaseous
material feed system can be put in a position to start a supply of
carbon dioxide gas preferentially over air. That is to say, simply
by turning on the main power switch, the gaseous material feed
system becomes ready to start a supply of carbon dioxide gas to a
body cavity.
[0021] As described above, from the standpoint of lessening damages
to a patient or examinee, the endoscopic gaseous material feed
system according to the present invention is adapted to take
preference of a carbon dioxide gas supply from a gas feeder over an
air supply from an air pump of a light source. At the time of
switching the gas feed from air to carbon dioxide gas, the air pump
is put in a deactivated state in synchronism with a start of supply
of carbon dioxide gas. Thus, the gas feed can be automatically
switched from air to carbon dioxide gas without necessitating to
manually turning off the air pump. This means that the system
according to the invention is particularly arranged to relieve an
operator of troublesome manual switching operations, with a view to
lessening burdens on the part of the operator.
BRIEF DESCRIPTION OF THE DRAWINGS
[0022] In the accompanying drawings:
[0023] FIG. 1 is a schematic view, showing a general layout of an
endoscopic gaseous material feed system embodying the present
invention;
[0024] FIG. 2 is a schematic sectional view of a
closed-to-atmosphere type fluid feed valve;
[0025] FIG. 3 is a block diagram showing configurative relations of
light source, processor and gas feeder; and
[0026] FIG. 4 is a schematic sectional view of a
closed-to-atmosphere type fluid feed valve.
DESCRIPTION OF PREFERRED EMBODIMENTS
[0027] Hereafter, the invention is described more particularly by
way of its preferred embodiments. Needless to say, the present
invention should not be construed as being limited to particular
examples shown. FIG. 1 schematically shows a general layout of a
gaseous material feed system according to the present invention,
which is largely constituted by an endoscope 1, a light source 2, a
gas feeder 3 and a processor 4 as described in greater detail
below. The endoscope 1 is introduced into a body cavity for the
purpose of medical examinations or treatments. Examples of the
endoscope 1 include not only flexible endoscopes in use in upper or
lower endoscopy but also rigid type endoscopes like a
laparoscope.
[0028] For instance, the endoscope 1 is used to give a medical
treatment in an endoscopic surgical operation. The light source 2
mainly serves as an illumination light source and incorporates an
air pump in its enclosure to supply air to a body cavity. The gas
feeder 3 is a carbon dioxide (CO.sub.2) gas source from which
carbon dioxide gas is supplied to a body cavity. The processor 4 is
adapted to perform video signal processing operations for
endoscopically captured picture images.
[0029] The endoscope 1 is largely composed of an elongated
insertion rod 11, a manipulating head assembly 12 and a universal
cable 13. The insertion rod 11 is so shaped as to permit
introduction into a body cavity of a patient or examinee under
control of manipulating and operating mechanisms on the
manipulating head assembly 12 to be gripped by an operator. A light
source connector 14 at a proximal end of the universal cable 13 is
disconnectibly connected to the light source 2. An illumination
window (not shown) and an observation window 15 are provided on a
fore distal end portion of the insertion rod 11 to capture the
observation window 15 images of an intracavitary site under
illumination by light projected through the illumination window. A
camera unit having an objective lens and a solid-state image sensor
device is fitted inside the observation window 15.
[0030] The endoscope 1 is internally provided with a fluid feed
mechanism. A liquid is supplied through the endoscope, for example,
at the time of washing the observation window 15 when contaminated
with body fluids, or at the time of cleaning intracavitary wall
surfaces prior to an examination or for the purpose of irrigative
cleaning. On the other hand, a gas is supplied to inflate a body
cavity or to dissipate liquid droplets from the observation window
15 after washing. In endoscopes in general, a fluid feed system is
adapted to supply water and air to a body cavity.
[0031] In this regard, the endoscope 1 is provided with a fluid
supply passage 16 internally through the insertion rod 11, the fore
distal end of the passage 16 being formed into the shape of a jet
nozzle 17 which is directed toward the observation window 15. This
fluid supply passage 16 in the insertion rod 11 is bifurcated into
a gas supply passage 18 and a liquid supply passage 19 on its way
and extended into the manipulating head assembly 12. The gas supply
passage 18 and liquid supply passage 19 are connected to a fluid
feed valve 20 which is provided internally of the manipulating head
assembly 12. The fluid feed valve 20 is connected with a gas feed
conduit 21 and a liquid feed conduit 22 which are brought into and
out of communication by operating the fluid feed valve 20.
[0032] A gas supply route is constituted by the above-mentioned gas
supply passage 18 and gas feed conduit 21, while a liquid supply
route is constituted by the above-mentioned liquid supply passage
19 and liquid feed conduit 22. Thus, the fluid supply passage 16
forms a common terminal passage for the gas supply passage and the
liquid supply passage to supply compressed air or a cleaning liquid
selectively to the jet nozzle 17. The gas feed conduit 21 and the
liquid feed conduit 22 are extended into the universal cable 13
from the manipulating head assembly 12, and led to the light source
connector 14.
[0033] An illumination lamp (not shown) is housed in the light
source 2 as a source of illumination light. By way of a light
guide, illumination light from this lamp is transferred as far as
an endoscopic observation means which is provided on a fore distal
end portion of the insertion rod 11. Thus, illumination light is
projected through the illumination window. Further, an electric
connector (not shown) is branched out from the universal cable 13
and disconnectibly connected to the processor 4.
[0034] An air pump 23 is built in the light source 2 to serve as a
source of compressed air under control of a pump control block 23c.
Connected to the air pump 23 is a compressed air pipe 24 through
which compressed air is delivered by operation of the air pump 23.
The liquid supply passage 19 serves as a cleaning liquid supply
route to supply a cleaning liquid from a liquid feed tank 25. This
liquid feed tank 25 is located outside the light source 2. A double
tube conduit 26 is connected to the liquid feed tank 25, the double
tube conduit 26 including an inner tube serving as a cleaning
liquid conduit 26a and an outer tube serving as a pressurization
conduit 26b. A piping connector member 27 which is attached to the
fore distal end of the double tube conduit 26 is disconnectibly
connected to a piping connector member 28 which is provided on the
side of the light source connector 14.
[0035] Of the double tube conduit 26, one end of the cleaning
liquid conduit 26a is immersed in a cleaning liquid in the liquid
feed tank 25, while one end of the pressurization conduit 26b is
opened into the tank 25 at a position above the surface of the
cleaning liquid. A gas feed conduit 29 which is connected from the
gas feeder 3 as a carbon dioxide gas supply route is connected to
the pressurization conduit 26b. Thus, the pressurization conduit
26b is bifurcated at a proximal end, one of the bifurcated ends
being connected to the gas feed conduit 29 and the other end being
led to the liquid feed tank 25. The pressurization conduit 26b is
connected to the gas feed conduit 29 and to a pressurization air
conduit 24 in the light source connector 14 to receive compressed
air from the air pump 23. Thus, a pressure is applied to the liquid
surface in the liquid feed tank 25 by introducing carbon dioxide
gas or air through the pressurization conduit 26b which is exposed
at an upper portion of the tank 25.
[0036] A fluid feed valve 20 and a suction valve 30 are provided on
the manipulating head assembly 12, along with a tool entrance way
31 for introduction of a surgical or biopsy tool. As exemplified in
FIG. 2, the fluid feed valve 20 is adapted to be manipulated by a
finger of a hand which grips the manipulating head assembly 12, for
selectively supplying a gas or liquid toward the jet nozzle 17. For
this purpose, a valve casing 40 is provided on the manipulating
head assembly 12 to accommodate the fluid feed valve 20 which is
connected to the gas supply passage 18 and the liquid supply
passage 19 on the side of the insertion rod 11 and to the gas feed
conduit 21 and the liquid feed conduit 22 on the side of the gas
and liquid sources as well. A valve guide 41 is fitted in the inner
periphery of the valve casing 40, and in turn a valve member 42 is
axially movably fitted in the valve guide 41. A switch button 43 is
attached to the outer end of the valve member 40 in such a way as
to project on the outer side of the valve casing 40.
[0037] The valve member 42 functions to open and close
communications between the gas supply passage 18 and the gas feed
conduit 21, and between the liquid supply passage 19 and the liquid
feed conduit 22. For this purpose, a first annular chamber C1, a
second annular chamber C2 and a third annular chamber C3 are
provided around the outer periphery of the valve guide 41. The
liquid feed conduit 22 is connected to the first annular chamber
C1, the liquid supply passage 19 is connected to the second annular
chamber C2, and the gas feed conduit 21 is connected to the third
annular chamber C3. Further, the gas supply passage 18 is opened
into the bottom of the valve casing 40, which is not covered with
the valve guide 41.
[0038] Communication passages R1 to R3 are bored axially through
the annular chambers C1 to C3, respectively. Further, the valve
member 42 is provided with a first switch portion S1 to switch on
and off communications between the liquid supply passage 19 and the
liquid feed conduit 22, along with a second switch portion S2 to
switch on and off communications between the gas supply passage 18
and the gas feed conduit 21. The first switch portion S1 is
constituted by a first annular passage 44 which is formed around
the outer periphery of the valve member 42; and the second switch
portion S2 is constituted by a second annular passage 45a formed
under the first annular passage 44, a communication hole 45b bored
axially through the valve member 42, and an axial passage 45c
opened in the bottom of the valve member 42.
[0039] In the position shown in FIG. 2, communication between the
gas supply passage 18 and the gas feed conduit 21 as well as
communication between the liquid supply passage 19 and the liquid
feed conduit 22 is blocked. If the switch button 43 is pushed in
from that position to lower the valve member 42, the gas supply
passage 18 and the gas feed conduit 21 are brought into
communication with each other through the first switch portion 21
in the course of a downward stroke. However, in this state,
communication between the liquid supply passage 19 and the liquid
feed conduit 22 is still blocked. That is to say, the fluid feed
valve 20 is now switched to a gas feed position. As the switch
button 43 is pushed in further toward a liquid feed position,
communication between the gas supply passage 18 and the gas feed
conduit 21 is blocked, and the liquid supply passage 19 and the
liquid feed conduit 22 are brought into communication with each
other through the first switch portion S1.
[0040] A return spring 47 is interposed between the valve member 42
and a spring holder 46 which is provided on the valve casing 40 to
bias the valve member 42 toward an outermost initial position.
Further, a spring holder 48 is attached on the valve member 42, and
a second spring member 49 is interposed between this spring holder
48 and the spring holder 46 to give a feeling of a stepwise
switching action. Therefore, when no external force is applied, the
switch button 43 is retained in the initial blocking position under
the influence of the biasing action of the return spring 47. Upon
pushing the switch button 43 inward against the action of the
return spring 47, the valve member 42 is axially slid along the
valve guide 41, switching the valve 20 to a gas feed position at a
middle point of the inward stroke of the valve member 42. Until
this gas feed position is reached, no biasing force is applied to
the valve member 42 from the second spring 49. As soon as the valve
member 42 is switched to the gas feed position, the lower side of
the switch button 43 is abutted against the spring holder 48.
Therefore, in order to further push down the valve member 42 from
this point, the switch button 43 needs to be pushed in against a
biasing force which increased by superposition of a biasing force
of the second spring 49. That is to say, by pushing down the switch
button 43 further against joined biasing forces of the return
spring 47 and the second spring 49, the valve member 42 is switched
to a liquid feed position.
[0041] The present invention is not limited to the particular
endoscopic fluid feed mechanism shown in the drawing. In the
particular example shown, as a liquid, a cleaning liquid is
supplied from the liquid feed tank 25. On the other hand, as a gas,
basically carbon dioxide gas is supplied through the mechanism.
However, if necessary, air is supplied from the air pump 23 which
is built in the light source 2. For this purpose, the present
invention adopts an endoscopic gaseous material feed system as
shown in FIG. 3. In this instance, in addition to the air pump 23,
the light source 2 is comprised of a light source controller 50, a
power switch 51, a pump switch 52 and a relief mechanism 53. By
operation of the pump 23, a pump pressure comes into effect to
supply compressed air to the pressurization conduit 24. The light
source controller 50 at the control of the air pump 23 is adapted
to make a decision as to whether or not activate the air pump 23 in
consideration of operating conditions.
[0042] The power switch 51 serves to turn on and off a power supply
to the light source 2. When the switch 51 is off, not only the air
pump 23 but also the supply of illumination light is turned off.
The pump switch 52 is provided to activate or deactivate the air
pump 23. Even when this switch 52 is off, the supply of
illumination light is kept on as long as the light source 2 is on.
The light source controller 50 is connected to the power switch 51
and the pump switch 52 to control the operation of the air pump 23.
The light source controller 50 is adapted to turn on the air pump
23 automatically when the power switch 51 is turned on, without
necessitating turning on the pump switch 52 separately.
[0043] The gas feeder 3 is loaded with a gas tank 60, and largely
constituted by a gas controller 61, a first regulator (REG1) 62, a
second regulator (REG2) 63, a valve 64, a check valve 65, a first
manometer (manometer 1) 66, a second manometer (manometer 2) 67, a
power switch 68, a residual content indicator 69, an alarm
indicator 70 and a valve switch 71. The gas tank 60 is packed with
carbon dioxide gas to serve as a source of carbon dioxide gas, and,
when emptied up or at a suitable timing, it can be dismantled and
replaced by a full one.
[0044] The gas controller 61 is at the control of the gas feeder 3
as a whole, including control of the power source or supply. The
first regulator 61 is connected to the gas tank 60 to reduce the
pressure of carbon dioxide gas from the gas tank 60. Since carbon
dioxide gas from the gas tank 60 is at a high pressure level, it is
reduced by two steps. That is to say, after a pressure reduction at
the first regulator 62, carbon dioxide is passed through the second
regulator 63 for a second pressure reduction. The valve 64 is
connected between the gas feed conduit 29 and the second regulator
63 through the check valve 65, and opened and closed to establish
or cut off communication with the gas feed conduit 29. As for the
valve 64, there may be employed an electromagnetic valve which is
capable of on-off control by energization and de-energization of a
solenoid. The check valve 65 is provided to block an inverse gas
flow from the side of the gas feed conduit 29.
[0045] The first manometer 66 plays the role of detecting the
pressure of carbon dioxide gas from the gas tank 60, while the
second manometer 67 plays the role of detecting the pressure of
carbon dioxide gas after a pressure reduction by the second
regulator 63. Detected gas pressures are output to the gas
controller 61 which is adapted to recognize a residual content of
the gas tank 60 on the basis of a gas pressure of the tank 60. The
power switch 68 is provided to turn on and off the power supply to
the gas feeder 3. The residual content indicator 69 is adapted to
indicate residual gas content as recognized by the gas controller
61. The alarm indicator 71 is adapted to indicate an alarm signal
or message in the event an abnormal pressure is detected by the
first manometer 66 or second manometer 67. If desired, the alarm
indicator 71 may be arranged to give off an alarm sound to draw
attention. The valve switch 71 is connected to the valve 64 to
manually open and close the latter. Basically, the valve 64 is
opened and closed under the control of the gas controller 61 but
can be manually opened and closed by means of the valve switch
71.
[0046] The processor 4 performs video signal processing operations
to generate video signals of endoscopically captured picture
images, on the basis electric signals of the solid-state image
sensor device on an endoscopic observation means at the fore distal
end of the insertion rod 11. Basically, the processor 4 is
configured to process video signals of endoscopically captured
picture images, but includes a controller 80 in control of the
light source controller 50 and the gas controller 61. For this
purpose, the light source 2 and the gas feeder 3 are connected with
each other by way of the processor 4, and the controller 80 is
connected with the light source controller 50 and the gas
controller 61 by the first and second communication lines 81 and
82. Further, the controller 80 in the processor 80 is adapted to
control the light source 2 and the gas feeder 3.
[0047] With the arrangements as described above, at the start of an
endoscopic examination or treatment using the endoscope 1, at least
illumination light needs to be fed to the endoscope 1 from the
light source 2. Therefore, in the first place, the power switch 51
is turned on to supply illumination light from the light source 2.
Besides, in this case, the air pump 23 is automatically started
when the power switch 51 is turned on. As a consequence, compressed
air is automatically supplied to the endoscope 1 as soon as the
light source 2 is turned on. However, if desired, arrangements may
be made to start the pump 23 afterwards by a manual operation on
the pump switch 52, instead of automatically starting same when the
power switch 51 of the light source 2 is turned on.
[0048] There are two feed gas sources, including the air pump 23 of
the light source 2 and carbon dioxide gas in the gas tank 60 of the
gas feeder 3. According to the present invention, from the
standpoint of lessening damages to a patient or examinee, the gas
feed system is arranged to take preference of a carbon dioxide gas
supply over an air supply. However, in consideration of an operator
or operators who are more accustomed to operations for an air
supply from the light source 2 than operations for a carbon dioxide
gas supply from the gas feeder 3, the gas feed system is arranged
to permit an air supply although priority is given to a carbon
dioxide gas supply.
[0049] The gas feeder 3 is put in operation when the power switch
68 is turned on by an operator. At this time, the turning-on of the
switch 68 is detected by the gas controller 61, and a switch-on
notice is sent to the controller 80 of the processor 4 via the
second communication line 82. Upon receiving the switch-on notice,
the controller 80 controls the light source controller 50 of the
light source 2 via the first communication line 81 to turn off the
air pump 23.
[0050] As described hereinbefore, the air pump 23 is started when
the light source 3 is turned on. Otherwise, the air pump 23 may
have been put in operation manually by way of the pump switch 52.
Therefore, the air pump 23 needs to be turned off to suspend an air
supply. However, in case the air pump 23 is not activated
automatically at the start or in case the air pump 23 is left in a
deactivated state by depression of the pump switch 52, the light
source controller 50 simply maintains the air motor 23 in a
deactivated state regardless of a control signal from the
controller 80 of the processor 4.
[0051] On the other hand, the gas controller 61 notifies the
turning-on of the power switch 68 and opens the valve 64. As a
consequence, carbon dioxide gas in the gas tank 60 is supplied from
the valve 64 to the geed gas conduit 20 after pressure reductions
by the first and second regulators 62 and 63, delivering the carbon
dioxide gas to the fluid feed valve 20 through the gas feed conduit
21. In case the fluid feed valve 20 is in a position to communicate
the gas feed conduit 21 with the gas supply passage 18, the carbon
dioxide gas is fed to a body cavity from the fore distal end of the
insertion rod 11.
[0052] At this time, since the air pump 23 is deactivated, air is
not supplied to the compressed air conduit 24 nor to the gas feed
conduit 21 to mix into carbon dioxide gas. As described above,
simply by depressing or turning on the power switch 68 of the gas
feeder 3, a supply of carbon dioxide gas is started while
suspending an air supply. That is, in switching a gas supply, there
is no need in particular for a switching action exclusively to turn
off the air pump 23. Besides, the automatic turn-off of the air
motor 23 contributes to prevent noises and unnecessary power
consumption which would result from redundant operation of the air
pump 23.
[0053] In this instance, the first communication line 81 which
connects the light source 2 with the processor 4 has been used in
existing systems for communication between the light source 2 and
the processor 4. An iris control circuit (not shown) which is
provided in the light source 2 is controlled from the processor 4
to adjust the light intensity. Therefore, the first communication
line 81 is provided at least for the iris control. On the other
hand, the gas feeder 3 should be connectible to various external
units, and for this purpose a connection interface is provided on
the gas feeder 3. Utilizing a connection interface of this sort,
the gas feeder 3 is connected with the processor 4 by the second
communication line 82.
[0054] As mentioned above, transmissions of information between the
processor 4 and the light source 2 can be made by the use of the
first communication line 81 which already exists. Therefore, there
is no need for specially making a new communication line. However,
it becomes necessary to introduce a new communication line for the
second communication line 82 which connects the gas feeder 3 with
the processor 4. Considering various controls which become
necessary between the processor 4 and the gas feeder 3, the second
communication line 82 can be utilized for transfer of necessary
information.
[0055] The controller 80 is adapted to turn off the air pump 23 of
the light source 2 when the power switch of the gas feeder 3 is
turned on, so that it is connected to processor 4 in addition to
the light source 2 and the gas feeder 3. For example, upon receipt
of a signal indicative of turning-on of the power switch (a
switch-on signal) through the second communication line 82 from the
gas controller 61, the controller 80 outputs this switch-on signal
to the light source controller 50. At this time, for example, the
switch-on signal is superposed on an iris control signal. In this
instance, the controller 80 is required to perform a signal
superposing operation.
[0056] The processors 4 is fundamentally a means for processing
video signals of endoscopically captured picture images, and for
this purpose includes a CPU which is capable of complicate
processing operations. Accordingly, it is possible to utilize part
of functions of the CPU for the above-described control by the
controller 80. In the particular embodiment shown, the controller
80 is connected to light source controller 50 and the gas
controller 61. However, it is also possible to connect the
controller 80 directly to the power switch 68 of the gas feeder 3
and the air pump 23 for the purpose of performing the
above-described control. In this case, the control is complicated
to some extent but can be easily executed by the use of the
processing means. The control by the gas feed system of the
invention can be realized without adding special control functions
to the light source 2 and the gas feeder 3.
[0057] By the way, in the foregoing exemplary embodiment, the valve
64 is opened and closed in interlinked relation with on and off of
the power switch 68. Therefore, a start of a carbon dioxide gas
supply is detected from a switch-on action on the power switch 68.
Of course, arrangements may be made to detect a start of a carbon
dioxide gas supply by other methods. As shown in FIG. 3, a supply
of carbon dioxide gas is started by opening the valve 64.
Therefore, it is possible to recognize a start of a carbon dioxide
gas supply by checking for opening of the valve 63 by the gas
controller 61. By so doing, a start of a carbon dioxide gas supply
can be recognized as soon as the valve 64 is opened by a manual
operation on the valve switch 71.
[0058] Now, described below is a control of the gas feeder 3
according to residual gas content in the tank 60. The internal
pressure of the gas tank 60 is constantly checked up by the first
manometer 66, and the detected readings in residual gas pressure
are output from the first manometer 66 to the gas controller 61. On
the basis of a detected pressure reading (residual gas pressure in
the gas tank 60), a residual gas content in the gas tank 60 is
detected by the gas controller 61. A value (a threshold value) of a
minimum necessary gas content for supply to a body cavity is preset
in the gas controller 61 for comparison with a detected residual
gas content. In this regard, arrangements may be made to compare
gas pressures instead of gas contents.
[0059] If the residual gas content drops below the threshold value,
it becomes difficult to inflate a body cavity to a sufficient
degree by a carbon dioxide gas supply or to apply a sufficient
pressure to the liquid surface in the liquid feed tank 25. In such
a case, the gas controller 61 closes the valve 64 to suspend a
carbon dioxide gas supply. At the same time, the suspension of a
gas supply is notified to the controller 80 through the second
communication line 2, whereupon the controller 80 controls the
light source controller to turn on the air pump 23 to start an air
supply. As a result, the air pump 23 is put in operation for an air
supply.
[0060] Thus, as soon as the residual gas content in the tank 60
drops below a minimum necessary gas content during an endoscopic
examination or treatment, the gas supply is automatically switched
from carbon dioxide to air. Since the residual content of carbon
dioxide gas in the tank 60 is limited, the gas supply is switched
from carbon dioxide gas to air when the residual gas content drops
below a predetermined threshold value, utilizing air which has
abundantly unlimited source. That is to say, carbon dioxide gas is
used as a main gas source while air is used as a supplementary gas
source. Accordingly, it becomes possible to continue an endoscopic
examination or treatment in an ordinary manner without facing a
total shutdown of gas supply.
[0061] By the way, normally the fluid feed valve 20 is held in a
closed position. Despite an increase in output pressure, the air
pump 23 acts to further increase the output pressure. Therefore,
the pressure can build up to an excessively high level by a
continued operation of the air pump 23. To cope with such
situations, the air pump 23 is provided with a relief mechanism 53
with a function of relieving excessively high pressures. More
specifically, the relief mechanism 55 is adapted to relieve an
excessively pressure when the pump pressure of the air pump 23
exceeds a predetermined relief point (a predetermined upper limit).
Accordingly, while the fluid feed valve 20 is held in a closed
position, the air pump 23 is put in operation at a maximum output
pressure.
[0062] In this instance, as shown in FIG. 2, the fluid feed valve
20 is of a closed-to-atmosphere type which is blocked against
communication with the atmosphere. However, in place of the fluid
feed valve 20 of FIG. 2 (a fluid feed valve which is blocked
against communication with the atmosphere), there may be employed
an open-to-atmosphere type fluid feed valve 120 (a fluid feed valve
which is communicable with the atmosphere) having an atmospheric
communication passage as shown in FIG. 4. The fluid feed valve 120
of FIG. 4 is built into the manipulating head assembly 12 in the
same manner as the fluid feed valve 20, including the valve casing
40, valve guide 41, gas supply passage 18, gas feed conduit 21,
liquid supply passage 19 and liquid feed conduit 22, but employs a
different valve member 142 in the valve guide 41 in place of the
valve member 42 of FIG. 2.
[0063] In the valve position shown in the drawing, a second annular
passage 145a at a second switching portion S2 of the valve member
142 is communicated with the gas supply passage 18 and the gas feed
conduit 21 through a communication hole 145b and an open passage
145c. At the same time, it is opened to the atmosphere through an
open passage 146 formed axially through the valve member 142 and
the switch button 143. Therefore, the air pump 23 can be put in
operation substantially in an idling state. If an outer end of the
open passage 146 is blocked by putting a finger on the switch
button 143, a pressure increase occurs at the second switch portion
S2 between the gas supply passage 18 and the gas feed conduit 21 to
supply air toward the gas supply passage 18. This is a gas feed
position of the fluid feed valve 120. As the valve member 142 is
further pushed down toward a liquid feed position against a biasing
force of a return spring 147, the communication between the gas
supply passage 18 and the gas feed conduit 21 is blocked, and
instead the liquid supply passage 19 and the liquid feed conduit 22
are brought into communication with each other.
[0064] In this manner, in use, the valve member 142 of the fluid
feed valve 120 is normally retained in an upper initial position
under the influence of the basing force of the return spring 147,
and can be switched to a gas feed position and a liquid feed
position by depressing the switch button 143 against the action of
the return spring 147 alone. Thus, in this case unlike the fluid
feed valve 20 of FIG. 2, the valve member 142 which is retained in
an upper initial position by the biasing action of the return
spring 147 is not switched stepwise to a gas feed position and a
liquid feed position firstly against the biasing force of the
return spring 147 and secondly against a combined biasing force of
the return spring 147 and a second biasing spring 49. That is to
say, in this case, it is necessary to apply the biasing force of
the return spring 147 to the valve member 142 there is no need for
providing the second biasing spring 49 and the spring holder
48.
[0065] Thus, the closed-to-atmosphere type fluid feed valve 20 can
be changed to the open-to-atmosphere type fluid feed valve 120 by
replacing the valve member 47 in the valve guide 41 by the valve
member 147. When the open-to-atmosphere type valve 120 is mounted,
carbon dioxide gas is constantly released to the atmosphere through
the open passage 146. Therefore, no matter whether the valve 120 is
in a gas feed position or liquid feed position, carbon dioxide gas
is wastefully consumed. However, depending upon familiarity with
manipulative control operations, an operator can turn off a gas
supply to prevent wasteful consumption of carbon dioxide gas
through the open-to-atmosphere type fluid feed valve 120.
[0066] On the other hand, in case an operator prefers use of carbon
dioxide gas, the closed-to-atmosphere type fluid feed valve 20 is
mounted in position thereby to prevent wasteful consumption of
carbon dioxide gas. Thus, depending upon whether or not an operator
prefers use of carbon dioxide gas, a suitable type of fluid feed
valve can be replaceably set on the endoscope to create optimum
conditions by a supply of a selected gas.
[0067] Further, the light source 2 and the gas feeder 3, which are
basically built as separate units, can be integrated into one
assembly unit if desired. No matter whether the light source 2 and
the gas feeder 3 are built as separate units or as one assembly
unit, they constitute and function as part of the endoscopic
gaseous material feed system of the invention. Therefore,
arrangements may be made to power on the light source 2 and the gas
feeder 3 when a power switch (not shown) of the gaseous material
feed system is turned on to start the respective components of the
system.
[0068] As described above, recently there is a trend toward using
carbon dioxide gas as a feed gas source in an endoscopic gaseous
material feed system. Therefore, it is desirable to control the gas
controller 61 of the gas feeder 3 to open the valve 64 for a supply
of carbon dioxide gas at the time when a power switch of the system
is turned on, while holding the air pump 23 of the light source 2
in a deactivated state. By so arranging, carbon dioxide gas is
preferentially supplied upon starting the system.
* * * * *